1. Field of Invention
This application generally relates to simulated firearms, specifically to simulated firearms which use blank cartridges.
2. Prior Art
Simulated firearms are safer substitutes of actual firearms for training, educational, recreational, and theatrical purposes. Simulated firearms resemble actual firearms and produce the realistic sound and visual effects of gunfire, without discharging lethal projectiles. Automatic simulated firearms are simulated firearms which generate the effects of gunfire in a repetitive manner.
There are several types of known simulated firearms. One type disclosed by U.S. Pat. No. 5,233,776 discharges squib explosive charges along the forward section of the simulated firearm. This device can operate as an automatic simulated firearm by employing multiple squib explosive charges. One disadvantage with the squib explosive charge device is that the report and flash are not generated through the muzzle of the simulated firearm. This makes the effect of the simulated gunfire unrealistic. Another disadvantage is that blank cartridges cannot be fed through a magazine nor ejected in a realistic manner. Since squib explosive charges are not contained in a detachable magazine, this device cannot be reloaded like a conventional firearm.
Another type of known automatic simulated firearm employs blank cartridges. This device operates by loading a blank cartridge from a magazine. The blank cartridge is chambered, discharged, and ejected. However this automatic simulated firearm does not discharge gases through the muzzle like an actual firearm. Instead the chamber has gas ports which vent gases in a lateral direction to the simulated firearm. This type of gas venting satisfies legal requirements for public sale in some jurisdictions. The disadvantage with this approach is that the flash and report are not realistically generated from the muzzle.
Actual firearms can be modified to use blank cartridges without discharging lethal projectiles, but there significant problems with this practice. Unmodified actual firearms can be loaded inadvertently with lethal ammunition and cause unintended damage and serious injury. When any blank cartridge is discharged, it is possible for part of the case to shear off. The detached portion of the blank cartridge can be projected through the barrel. Such projectiles have caused serious injury and death.
A further problem with discharging blanks from actual automatic firearms is that blank cartridges typically fail to generate sufficient gas pressure and/or recoil to cycle the action. Without a projectile, the gas and recoil pressures are much lower when a blank cartridge is discharged instead of a lethal cartridge. Modifications have been developed for automatic firearms to elevate the gas pressure and recoil to allow the simulated firearm to cycle with blank ammunition. One type of adapter for gas operated automatic firearms attaches the simulated firearm muzzle, as disclosed by U.S. Pat. No. 6,026,728. Another adapter employs a barrel insert to elevate gas pressure by means of a barrel insert, as disclosed by U.S. Pat. No. 5,585,589. Both the muzzle adapter and barrel insert can be combined, as disclosed by U.S. Pat. No. 4,499,811. Another device is a barrel with a ported chamber in which the chamber ports bleed gas pressure to prevent the discharge of a lethal projectile. An example is disclosed by U.S. Pat. No. 5,937,563. With respect to recoil operated firearms, one modification elevates recoil through a barrel sleeve device, as disclosed by U.S. Pat. No. 4,907,489. Barrel insert adapters have been used for recoil operated automatic firearms, as disclosed by U.S. Pat. No. 5,585,589.
All types of blank modifications for actual firearms have inherent disadvantages. As firearms, actual firearms are subject to extensive legal restrictions governing their sale, possession, and use. External modifications detract from the realistic appearance of simulated or actual firearms firearm. In most types of adapters, the inadvertent discharge of a lethal cartridge will likely damage the adapter and firearm. Any projectile, whether from a lethal cartridge or a detached portion of a blank cartridge, may cause result in death or serious injury. Modifications can be removed, altered, or fail, thereby returning the actual firearm to its original lethal capability.
3. Objects and Advantages
Accordingly several objects and advantages of the present invention are:                (a) to realistically generate a flash and report simulating gunfire;        (b) to be incompatible with lethal cartridges;        (c) to prevent the discharge of projectiles;        (d) to be capable of loading, chambering, discharging, and ejecting blank cartridges in a safe and realistic manner;        (e) to discharge blank cartridges more reliably; and        (f) to operate in a manner not restricted by legal regulations governing the sale, use, and possession of actual firearms.        
Further objects and advantages will become apparent from a consideration of the ensuing description and drawings.